Compounds of formula (5), optionally in the form of the tautomers thereof, are valuable intermediates in methods for the stereoselective preparation of the compound of formula (I), optionally in the form of the tautomers thereof, and optionally the pharmacologically acceptable acid addition salts thereof,
which compound has valuable pharmacological properties, particularly an inhibiting action on signal transduction mediated by tyrosine kinases, and for the treatment of diseases, particularly tumoral diseases, benign prostatic hyperplasia and diseases of the lungs and respiratory tract.
Quinazoline derivatives are known from the prior art as active substances for example for the treatment of tumoral diseases and also diseases of the lungs and airways. Methods for preparing quinazoline derivatives are described in WO2003082290 and WO2007068552. WO2009098061 and WO2011015526 disclose methods of preparing the compound (I).
The problem of the present invention is to provide an alternative stereoselective synthesis process for preparing the compound of formula (I) or an advantageous method of preparing important intermediates of this synthesis.